{"cve":"CVE-2025-69873","nvd":{"published":"2026-02-11T19:15:50.467","modified":"2026-09-10T13:17:29.420","status":"Deferred","description":"ajv (Another JSON Schema Validator) before 8.18.0 is vulnerable to Regular Expression Denial of Service (ReDoS) when the $data option is enabled. The pattern keyword accepts runtime data via JSON Pointer syntax ($data reference), which is passed directly to the JavaScript RegExp() constructor without validation. An attacker can inject a malicious regex pattern (e.g., \"^(a|a)*$\") combined with crafted input to cause catastrophic backtracking. A 31-character payload causes approximately 44 seconds of CPU blocking, with each additional character doubling execution time. This enables complete denial of service with a single HTTP request against any API using ajv with $data: true for dynamic schema validation. This issue is also fixed in version 6.14.0.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","score":2.9},"cwes":["CWE-1333","CWE-400"],"references":["https://github.com/EthanKim88/ethan-cve-disclosures/blob/main/CVE-2025-69873-ajv-ReDoS.md","https://github.com/advisories/GHSA-2g4f-4pwh-qvx6","https://github.com/ajv-validator/ajv/pull/2588","https://github.com/ajv-validator/ajv/pull/2590","https://github.com/ajv-validator/ajv/releases/tag/v6.14.0"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:23:35.260773158+00:00"},"epss":{"cve":"CVE-2025-69873","score":0.00547,"percentile":0.45847,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-2g4f-4pwh-qvx6","url":"https://osv.dev/vulnerability/GHSA-2g4f-4pwh-qvx6","summary":"ajv has ReDoS when using `$data` option","modified":"2026-09-10T03:50:33.716487588Z","packages":[{"ecosystem":"npm","name":"ajv","purl":"pkg:npm/ajv","ranges":[">=7.0.0-alpha.0 <8.18.0"],"fixed":["8.18.0"]},{"ecosystem":"npm","name":"ajv","purl":"pkg:npm/ajv","ranges":["<6.14.0"],"fixed":["6.14.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}